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.TH PTHREAD_SPIN_LOCK 3C "Jan 30, 2004"
.SH NAME
pthread_spin_lock, pthread_spin_trylock \- lock a spin lock object
.SH SYNOPSIS
.LP
.nf
cc \fB-mt\fR [ \fIflag\fR... ] \fIfile\fR... [ \fIlibrary\fR... ]
#include <pthread.h>

\fBint\fR \fBpthread_spin_lock\fR(\fBpthread_spinlock_t *\fR\fIlock\fR);
.fi

.LP
.nf
#include <pthread.h>

\fBint\fR \fBpthread_spin_trylock\fR(\fBpthread_spinlock_t *\fR\fIlock\fR);
.fi

.SH DESCRIPTION
.sp
.LP
The \fBpthread_spin_lock()\fR function locks the spin lock referenced by
\fIlock\fR. The calling thread acquires the lock if it is not held by another
thread. Otherwise, the thread spins (that is, does not return from the
\fBpthread_spin_lock call()\fR) until the lock becomes available. The results
are undefined if the calling thread holds the lock at the time the call is
made.
.sp
.LP
The \fBpthread_spin_trylock()\fR function locks the spin lock referenced by
\fIlock\fR if it is not held by any thread. Otherwise, the function fails.
.sp
.LP
The results are undefined if either of these functions is called with an
uninitialized spin lock.
.SH RETURN VALUES
.sp
.LP
Upon successful completion, these functions returns 0. Otherwise, an error
number is returned to indicate the error.
.SH ERRORS
.sp
.LP
The \fBpthread_spin_trylock()\fR function will fail if:
.sp
.ne 2
.na
\fB\fBEBUSY\fR\fR
.ad
.RS 9n
A thread currently holds the lock.
.RE

.sp
.LP
These functions may fail if:
.sp
.ne 2
.na
\fB\fBEINVAL\fR\fR
.ad
.RS 10n
The value specified by \fIlock\fR does not refer to an initialized spin lock
object.
.RE

.sp
.LP
The \fBpthread_spin_lock()\fR function may fail if:
.sp
.ne 2
.na
\fB\fBEDEADLK\fR\fR
.ad
.RS 11n
The calling thread already holds the lock.
.RE

.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(7) for descriptions of the following attributes:
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
Interface Stability	Standard
_
MT-Level	MT-Safe
.TE

.SH SEE ALSO
.sp
.LP
.BR pthread_spin_destroy (3C),
.BR pthread_spin_unlock (3C),
.BR attributes (7),
.BR standards (7)
